The workflow management system provides automatic management and execution of workflows that include both automated and user-driven actions. The system monitors connected external systems and/or users for the occurrence of events, which trigger the execution of one or more workflow plans. Each workflow plans consists of a plurality of actions and user actions to be performed in a sequential manner. Actions are executed automatically by the system, but user actions are executed asynchronously due to the inclusion of users in the workflow plan. The system handles the asynchronous nature of user actions by maintaining a pending user action database that users can access to view pending user actions, complete user actions, and reserve user actions for subsequent completion.